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<base href="https://bugs.llvm.org/">
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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - Rejects valid code claiming "pack expansion does not contain any unexpanded parameter packs""
href="https://bugs.llvm.org/show_bug.cgi?id=42766">42766</a>
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<th>Summary</th>
<td>Rejects valid code claiming "pack expansion does not contain any unexpanded parameter packs"
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<th>Product</th>
<td>clang
</td>
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<th>Version</th>
<td>trunk
</td>
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<th>Hardware</th>
<td>PC
</td>
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<th>OS</th>
<td>Linux
</td>
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<th>Status</th>
<td>NEW
</td>
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<th>Severity</th>
<td>enhancement
</td>
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<th>Priority</th>
<td>P
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<th>Component</th>
<td>C++17
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<th>Assignee</th>
<td>unassignedclangbugs@nondot.org
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<th>Reporter</th>
<td>david@doublewise.net
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<th>CC</th>
<td>blitzrakete@gmail.com, erik.pilkington@gmail.com, llvm-bugs@lists.llvm.org, richard-llvm@metafoo.co.uk
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<p>
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<pre>The following well-formed translation unit is rejected by clang as invalid.
template<typename>
bool false_ = false;
struct outer_traits {
using type = int;
};
template<typename... RangeViews>
struct s {
template<typename RangeView>
using traits = outer_traits;
static bool any = (... or false_<typename traits<RangeViews>::type>);
};
clang (all versions that have a -std=c++17 flag) outputs:
<source>:13:21: error: pack expansion does not contain any unexpanded parameter
packs
static bool any = (... or false_<typename traits<RangeViews>::type>);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
Compiler returned: 1
See it live: <a href="https://godbolt.org/z/L84t58">https://godbolt.org/z/L84t58</a></pre>
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